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From: Erik Naggum
Subject: Re: [N]TRUNCATE-LIST ?
Date: 2000/02/11
Message-ID: <3159291352590096@naggum.no>#1/1
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* Philip Lijnzaad
| after some browsing in the HyperSpec, I couldn't find a function that yields,
| as a list, the first N elts of the list passed as an argument, sort of the
| opposites of [N]BUTLAST.
have you looked at SUBSEQ for the non-destructive version? or a fairly
plain SETF of NTHCDR for a destructive version? if you have to check for
the length, use NTHCDR, see if you get a cons cell, then SETF its CDR.
there's absolutely _no_ need to check the length of the list, which,
incidentally, may be circular, so use LIST-LENGTH instead of LENGTH if
you think you really have to.
#:Erik